2-47801030-C-T

Position:

• chr2-47801030-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000179.3(MSH6):​c.3047C>T​(p.Ala1016Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MSH6 NM_000179.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 2.57

Genes affected

MSH6 (HGNC:7329): (mutS homolog 6) This gene encodes a member of the DNA mismatch repair MutS family. In E. coli, the MutS protein helps in the recognition of mismatched nucleotides prior to their repair. A highly conserved region of approximately 150 aa, called the Walker-A adenine nucleotide binding motif, exists in MutS homologs. The encoded protein heterodimerizes with MSH2 to form a mismatch recognition complex that functions as a bidirectional molecular switch that exchanges ADP and ATP as DNA mismatches are bound and dissociated. Mutations in this gene may be associated with hereditary nonpolyposis colon cancer, colorectal cancer, and endometrial cancer. Transcripts variants encoding different isoforms have been described. [provided by RefSeq, Jul 2013]

FBXO11 (HGNC:13590): (F-box protein 11) This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbxs class. It can function as an arginine methyltransferase that symmetrically dimethylates arginine residues, and it acts as an adaptor protein to mediate the neddylation of p53, which leads to the suppression of p53 function. This gene is known to be down-regulated in melanocytes from patients with vitiligo, a skin disorder that results in depigmentation. Polymorphisms in this gene are associated with chronic otitis media with effusion and recurrent otitis media (COME/ROM), a hearing loss disorder, and the knockout of the homologous mouse gene results in the deaf mouse mutant Jeff (Jf), a single gene model of otitis media. Alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene. [provided by RefSeq, Jun 2010]

MSH6 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.34992597).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MSH6	NM_000179.3	c.3047C>T	p.Ala1016Val	missense_variant	4/10	ENST00000234420.11	NP_000170.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MSH6	ENST00000234420.11	c.3047C>T	p.Ala1016Val	missense_variant	4/10	1	NM_000179.3	ENSP00000234420.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Oct 08, 2018	Variant summary: MSH6 c.3047C>T (p.Ala1016Val) results in a non-conservative amino acid change located in the DNA mismatch repair protein MutS, core domain of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 222900 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.3047C>T in individuals affected with Lynch Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. A ClinVar submission from a clinical diagnostic laboratory (evaluation after 2014) cites variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Feb 03, 2017	- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Dec 30, 2013

This variant is denoted MSH6 c.3047C>T at the cDNA level, p.Ala1016Val (A1016V) at the protein level, and results in the change of an Alanine to a Valine (GCT>GTT). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. MSH6 Ala1016Val was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This variant is a conservative substitution of one neutral non-polar amino acid for another, altering a position that is well conserved throughout evolution and is not located in a known functional domain. In silico analyses are inconsistent with regard to the effect this variant may have on protein structure and function. Based on currently available information, it is unclear whether MSH6 Ala1016Val is pathogenic or benign. We consider it to be a variant of uncertain significance. -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 09, 2023

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MSH6 protein function. ClinVar contains an entry for this variant (Variation ID: 127577). This variant has not been reported in the literature in individuals affected with MSH6-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1016 of the MSH6 protein (p.Ala1016Val). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 10, 2022

The p.A1016V variant (also known as c.3047C>T), located in coding exon 4 of the MSH6 gene, results from a C to T substitution at nucleotide position 3047. The alanine at codon 1016 is replaced by valine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Uncertain	0.073	D
BayesDel_noAF	Benign	-0.13
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.59	.;.;D;T;.
Eigen	Benign	0.10
Eigen_PC	Benign	0.21
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.88	.;D;D;D;D
M_CAP	Uncertain	0.10	D
MetaRNN	Benign	0.35	T;T;T;T;T
MetaSVM	Uncertain	0.33	D
MutationAssessor	Benign	1.9	.;.;L;.;.
PrimateAI	Benign	0.45	T
PROVEAN	Benign	-1.9	.;N;N;.;N
REVEL	Uncertain	0.33
Sift	Benign	0.098	.;T;T;.;T
Sift4G	Benign	0.17	T;T;T;T;T
Polyphen		0.25	.;.;B;.;.
Vest4		0.46
MutPred		0.44		.;.;Loss of disorder (P = 0.109);.;.;
MVP		0.92
ClinPred		0.79	D
GERP RS		4.9
Varity_R		0.25
gMVP		0.50

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs587779929; hg19: chr2-48028169;